Torch for Numpy users

torch equivalents of numpy functions

Types

Numpy	Torch
np.ndarray	torch.Tensor
np.float32	torch.FloatTensor
np.float64	torch.DoubleTensor
np.int8	torch.CharTensor
np.uint8	torch.ByteTensor
np.int16	torch.ShortTensor
np.int32	torch.IntTensor
np.int64	torch.LongTensor

Constructors

Ones and zeros

Numpy	Torch
np.empty([2,2])	torch.Tensor(2,2)
np.empty_like(x)	x.new(x:size())
np.eye	torch.eye
np.identity	torch.eye
np.ones	torch.ones
np.ones_like	torch.ones(x:size())
np.zeros	torch.zeros
np.zeros_like	torch.zeros(x:size())

From existing data

Numpy	Torch
np.array([ [1,2],[3,4] ])	torch.Tensor({{1,2},{3,4}})
np.ascontiguousarray(x)	x:contiguous()
np.copy(x)	x:clone()
np.fromfile(file)	torch.Tensor(torch.Storage(file))
np.frombuffer	???
np.fromfunction	???
np.fromiter	???
np.fromstring	???
np.loadtxt	???
np.concatenate	torch.cat
np.multiply	torch.cmul

Numerical Ranges

Numpy	Torch
np.arange(10)	torch.range(0,9)
np.arange(2, 3, 0.1)	torch.linspace(2, 2.9, 10)
np.linspace(1, 4, 6)	torch.linspace(1, 4, 6)
np.logspace	torch.logspace

Building Matrices

Numpy	Torch
np.diag	torch.diag
np.tril	torch.tril
np.triu	torch.triu

Attributes

Numpy	Torch
x.shape	x:size()
x.strides	x:stride()
x.ndim	x:dim()
x.data	x:data()
x.size	x:nElement()
x.size == y.size	x:isSameSizeAs(y)
x.dtype	x:type()

Indexing

Numpy	Torch

Shape Manipulation

Numpy	Torch
x.reshape	x:reshape
x.resize	x:resize
?	x:resizeAs
x.transpose	x:transpose()
x.flatten	x:view(x:nElement())
x.squeeze	x:squeeze

Item selection and manipulation

Numpy	Torch
np.take(a, indices)	a[indices]
x[:,0]	x[{{},1}]
np.put	????
x.repeat	x:repeatTensor
x.fill	x:fill
np.choose	???
np.sort	sorted, indices = torch.sort(x, [dim])
np.argsort	sorted, indices = torch.sort(x, [dim])
np.nonzero	torch.find(x:gt(0), 1) (torchx)

Calculation

Numpy	Torch
ndarray.min	mins, indices = torch.min(x, [dim])
ndarray.argmin	mins, indices = torch.min(x, [dim])
ndarray.max	maxs, indices = torch.max(x, [dim])
ndarray.argmax	maxs, indices = torch.max(x, [dim])
ndarray.clip	torch.clamp
ndarray.round
ndarray.trace	torch.trace
ndarray.sum	torch.sum
ndarray.cumsum	torch.cumsum
ndarray.mean	torch.mean
ndarray.std	torch.std
ndarray.prod	torch.prod
ndarray.dot	torch.mm
ndarray.cumprod	torch.cumprod
ndarray.all	???
ndarray.any	???

Arithmetic and comparison operations

Numpy	Torch
ndarray.lt	torch.lt
ndarray.le	torch.le
ndarray.gt	torch.gt
ndarray.ge	torch.ge
ndarray.eq	torch.eq
ndarray.ne	torch.ne